perf(const): const changed to a singelton

const needds to be accessed all throughout so it has been changed to a singleton to allow for more efficient usage

BREAKING CHANGE: Any previous loads to const will break, also constant->Constant and constants->Constants

src/const/private/const.cpp

@@ -3,23 +3,22 @@
 #include <vector>
 #include <string>
 #include <fstream>
+#include <sstream>
 #include <set>
 
+
 #include "const.h"
+#include "embedded_constants.h" // Generated at build time by meson
 
-constants::constants() {
-  loaded_ = false;
+Constants::Constants() {
+  loaded_ = initialize();
 }
 
-constants::constants(const std::string& filename) {
-  loaded_ = initialize(filename);
+bool Constants::initialize() {
+  return load();
 }
 
-bool constants::initialize(const std::string& filename) {
-  return load(filename);
-}
-
-constant constants::get(const std::string& name) const {
+Constant Constants::get(const std::string& name) const {
   auto it = constants_.find(name);
   if (it != constants_.end()) {
     return it->second;
@@ -28,15 +27,15 @@ constant constants::get(const std::string& name) const {
   }
 }
 
-constant constants::operator[](const std::string& name) const {
+Constant Constants::operator[](const std::string& name) const {
   return this->get(name);
 }
 
-bool constants::has(const std::string& name) const {
+bool Constants::has(const std::string& name) const {
   return constants_.find(name) != constants_.end();
 }
 
-std::set<std::string> constants::keys() const {
+std::set<std::string> Constants::keys() const {
   std::set<std::string> keys;
   for (const auto& pair : constants_) {
     keys.insert(pair.first);
@@ -44,32 +43,28 @@ std::set<std::string> constants::keys() const {
   return keys;
 }
 
-std::string constants::trim(const std::string& str) {
+std::string Constants::trim(const std::string& str) {
     size_t first = str.find_first_not_of(" \t");
     if (first == std::string::npos) return "";
     size_t last = str.find_last_not_of(" \t");
     return str.substr(first, last - first + 1);
 }
 
-bool constants::load(const std::string& filename) {
-    std::ifstream file(filename);
-    if (!file.is_open()) {
-        std::cerr << "Error: Unable to open file " << filename << std::endl;
-        return false;
-    }
+bool Constants::load() {
+    std::istringstream fileStream(embeddedConstants);
 
     std::string line;
     bool data_section = false;
     int line_count = 0;
 
-    while (std::getline(file, line)) {
+    while (std::getline(fileStream, line)) {
         line_count++;
 
         // Detect start of data section (double divider line)
         if (!data_section) {
             if (line.find("Symbol") != std::string::npos) {  // Find header row
-                std::getline(file, line);  // Skip dashed divider
-                std::getline(file, line);  // Skip second dashed divider
+                std::getline(fileStream, line);  // Skip dashed divider
+                std::getline(fileStream, line);  // Skip second dashed divider
                 data_section = true;
             }
             continue;
@@ -102,10 +97,8 @@ bool constants::load(const std::string& filename) {
         }
 
         // Store in map
-        constants_.emplace(symbol, constant{name, value, uncertainty, unit, reference});
+        constants_.emplace(symbol, Constant{name, value, uncertainty, unit, reference});
     }
-
-    file.close();
     loaded_ = true;
     return true;
 }